1. Field of the Invention
The present invention relates to the textile industry and, more particularly, to systems, devices, and methods of producing yarn.
2. Description of Related Art
In the textile industry, various systems have been developed over the years for producing texturized and straight set yarn in a high speed, continuous production process such as for use in carpet related products or other textile products. Many systems often include a yarn supply, a false twister positioned downstream from the yarn supply to impact a false twist to the yarn to enhance cohesiveness, one or more draw rolls positioned downstream from the false twister, a stuffer box or stuffer can to crimp or otherwise form a texture in the yarn, a yarn conveyor belt positioned downstream from the stuffer box and positioned to receive the yarn thereon to convey the yarn downstream, a bulker positioned to receive the yarn conveyor and to initially heat bulk the yarn, a yarn conveyor retainer band or counterband positioned to overlie the bulked yarn to enhance retaining the bulked yarn on the yarn conveyor belt, a heat setting oven positioned to receive the yarn conveyor belt having the retained and bulked yarn, a yarn cooler, e.g., a fan(s), positioned downstream from the heat setting oven to cool the yarn, and a yarn take-up positioned downstream from the yarn cooler and the heat setting oven to take-up the yarn from the yarn conveyor belt.
In these prior art systems, textile yarns, especially carpet yarns are twisted and plied into a spiral shape prior to being used to form the finished product, such as carpet. The finished carpet appearance and performance depends upon the durability of the twist. Heat setting changes the molecular structure of the yarn, making the twist substantially permanent.
In prior systems, a counterband is used in conjunction with the heat setting oven to help hold the bundle of yarn against the conveyor belt as the bundle of yarn is heat set with the heat setting oven and the yarn cooler. The traditional counterband is constructed from woven textile webbing. The textile webbing is uncoated, and typically narrow in width (a few inches wide), such that the counterband resembles a seat belt.
The counterband is utilized to hold the bundle of yarn in place as the conveyor carries it through the heat setting oven and the yarn cooler. There are several places and mechanisms by which the yarn can become displaced or snagged, which reduces the production efficiency of the entire system. At each end of a steam chamber of the heat setting oven, there is a set of rollers, or “pinch” rollers, that squeeze the yarn, the counterband and the conveyor belt. The rollers substantially seal the chamber at both ends, preventing the pressurized steam from escaping. As the rollers are constantly exposed to the steam and moisture associated therewith, the yarn often sticks to the rollers.
The yarn can also become displaced simply by application of the steam within the heat setting oven. Inside the steam chamber, there is an active circulation of steam that passes up through the conveyor and through the bundle of yarn. The flow of the steam tends to lift the yarn off the conveyor, which the counterband is supposed to help reduce.
Previous counterbands did not cover the entire width of the bundle of yarn such that the yarn was displaced from the conveyor by the steam in the heat setting oven. Previous counterbands also had a “closed” weave pattern with very low porosity, thereby inhibiting the flow of the steam through the counterband. Previous counterbands also comprised uncoated textile webbing that tends to absorb chemicals from the bundle of yarn being processed. Moreover, the previous counterbands absorb moisture associated with the steam, become soaked with moisture almost immediately upon start-up, and stay wet for the duration of the operation. The wet textile counterband cools off as it travels from the exit of the heat setting oven to the entrance of the heat setting oven, but it does not dry. The cold, wet textile counterband inhibits the ability of the steam to heat the bundle of yarn. With previous counterbands that did not cover the entire with of the bundle of yarn, the heat setting of the bundle of yarn varied across the width of the bundle of yarn due to the wet counterband inhibiting the heat setting of the portions of the bundle of yarn which the counterband contacted. When the heat setting is not uniform, the bundle of yarn is not uniform. Pattern defects (sometimes referred to as “streaks” or “chevron”) form in the finished product, such as carpet. Such defects are highly objectionable.
The previous counterbands were also hot and wet upon exiting the heat setting oven. The counterband stays on top of the bundle of yarn as it moves into the cooling zone associated with the yarn cooler. Because the heat was retained in the moisture absorbed by previous counterbands, the previous counterbands reduced the efficiency and the ability of the yarn coolers to quickly cool the bundle of yarn.
In the present application, the speed of producing yarn can be significantly slower than other types of yarn production, such as straight set. It is thought that this difference in some circumstances can be as much as 20% slower for texturized production than for straight set production. As a result, more labor, more production shifts, longer production times, and/or more machine wear and tear can be required to achieve desired yarn production results. Applicant therefore has recognized a need to reduce production loss and increase production speed for yarn, especially in continuous yarn production processes.